The MCQST Colloquium Series features interdisciplinary talks given by visiting international speakers. The monthly colloquium covers topics spanning all MCQST research units and will be broadcast live via Zoom for audiences worldwide. The main goal of the series is to create the framework for idea exchange, to strengthen links with QST leading groups worldwide, as well as to act as an integral part of the local educational environment.

MCQST Colloquium: Audrey Bienfait

We are excited to invite you to the colloquium talk by Audrey Bienfait (École Normale Supérieure de Lyon, France).

Agenda

14:00 | Teaser talk by Ana Strinic (WMI) on "Characterization of hyperfine transitions of rare earth spin ensembles via broadband ESR spectroscopy"

14:15 | Coffee break

14:30 | Colloquium talk by Audrey Bienfait on “Implementing a quantum memory with a frequency and bandwidth-tuneable superconducting resonator”

Implementing a quantum memory with a frequency and bandwidth-tuneable superconducting resonator

Among platforms for storing quantum states in the microwave domain, solid state spin ensembles addressed via superconducting circuits stand out for their multimodal storage capability and the second-long coherence time when operated at clock transitions [Wolfowicz, G. et al. Nature nanotechnology 8, 561–564 (2013)].

Successful implementation of a practical memory scheme requires several keys features, such as the ability to tune on-demand the frequency and the bandwidth of the superconducting circuit [Julsgaard, B. et al. Phys. Rev. Lett. 110, 250503 (2013)]. In this talk, I will present an architecture accomplishing both, and strong coupling to an ensemble of bismuth donors in silicon. I will also show how this circuit enables radiative relaxation of the spins and allows us to implement in-situ nuclear level cooling. We will finish by assessing the ability of the system to implement a quantum memory.

References:
[1] Wolfowicz, G. et al. Nature nanotechnology 8, 561–564 (2013).
[2] Julsgaard, B. et al. Phys. Rev. Lett. 110, 250503 (2013).

About Audrey Bienfait

Audrey Bienfait completed her Ph.D. in the Quantronics group in CEA Saclay (France) in 2016. Her experimental work applied circuits quantum electrodynamics techniques to electron spin resonance and improved the spin signal detection sensitivity by four-order-of-magnitude and implemented a spin initialization mechanism via the Purcell effect. She then realized a post-doc in the Cleland group at the University of Chicago (USA), where she coupled remote superconducting qubits using traveling phonons and realized acoustic interferometry experiments. In 2019, she joined ENS Lyon as a CNRS researcher. Her current research interests are electronic spins, and superconducting circuits, exploring their potential for quantum memories schemes and for probing the magnetic response of matter at the micron-scale.

Join in-person or via Zoom

https://lmu-munich.zoom-x.de/j/61426372835?pwd=EmtzIxaTglfP30KabEzreCos1pKva6.1

Meeting ID: 614 2637 2835, Passcode: mcqst2025